Socio-economic drivers and synergistic governance of haze and ozone pollution in three major urban agglomerations in China

Abstract To effectively analyze and address the synergistic governance of haze and ozone pollution in China, this study adopts a socio-economic perspective. Utilizing the Logarithmic Mean Divisia Index decomposition model, we quantified the theoretical emission reduction effects of various driving factors on PM 2.5 and O 3 concentrations (ρ(PM 2.5 ) and ρ(O 3 )) in three major urban agglomerations: Beijing-Tianjin-Hebei, Yangtze River Delta, and Pearl River Delta. Based on these findings, we projected the medium-to-long-term trends of PM 2.5 and O 3 concentrations through scenario analysis. The study found that: (1) During the period of 2015–2022, haze pollution showed comprehensive and significant improvement across the three major urban agglomerations, while ozone pollution exhibited recurrent N-shaped variation patterns. (2) Effective haze pollution control in the three major urban agglomerations was driven predominantly by emission intensity effects, with supplementary contributions from industrial structure optimization and technological advancement. Conversely, the ozone reduction pattern, characterized by technological advancement as the primary driver alongside oscillating positive-negative effects from industrial restructuring and emission intensity, ultimately failed to control rising O 3 concentrations. (3) Projected toward 2035, decrease of ρ(PM 2.5 ) and ρ(O 3 ) in the three major urban agglomerations is high-quality development scenario > energy-saving scenario > technological progress scenario > industrial structure optimization scenario > baseline scenario > extensive development scenario. For future synergistic governance of haze and ozone pollution, priority should be given to the S5 high-quality development model, while addressing rebound effects from socio-economic drivers during pollution mitigation.